1. Field of the Invention
The present invention relates to electroacoustic transducers such as speakers and microphones.
This application claims priority on Japanese Patent Application No. 2006-222382, the content of which is incorporated herein by reference.
2. Description of the Related Art
Conventionally, it is required that electroacoustic transducers such as speakers and microphones be reduced in size and weight. U.S. Patent Application Publication No. 2003/0044029 teaches an example of an electroacoustic transducer adapted to MEMS technology. This kind of electroacoustic transducer is formed using a fixed electrode (having a planar shape) and a diaphragm electrode, wherein the peripheral portions of the fixed electrode and diaphragm electrode are fixed to a ring-shaped housing and are thus positioned opposite to each other with a spacing therebetween, and wherein the fixed electrode and diaphragm electrode are arranged inside of the housing.
When the electroacoustic transducer having the aforementioned constitution serves as a speaker, the diaphragm electrode vibrates due to elastic deformation in response to a certain voltage being applied between the fixed electrode and the diaphragm electrode.
Since the peripheral portion of the diaphragm electrode is fixed in the aforementioned electroacoustic transducer, it is very difficult to produce adequate amplitude when the electroacoustic transducer serves as a speaker; hence, it is very difficult to produce sound having high sound pressure.